1. Field of the Invention
This invention relates to a method and apparatus for facilitating the interchange of data among processors in a multiprocessing environment. In particular, an optical data switch which permits each processor to talk with all other processors is disclosed.
2. Background Information
A multiprocessor computer is one in which the calculating task is divided up among several, sometimes many similar processor elements. The processors are often logically arranged in a geometric pattern such as, for example, the squares on a checkerboard. The difficulty of making electrical connections among processors, especially when the number of them is large, has forced a compromise which allows a processor to communicate directly with only its geometrically adjacent neighbors.
This approach solves the interconnection problem, but forces some severe constraints on the applications software which is to run in this environment. The software must not only lend itself to being broken up into modules that can execute in parallel, but also these modules must interrelate in such a way that any external data that they require must be available from an adjacent processor. Thus, the geometry of the computer weighs heavily on the final form of the software. If the applications software must deviate from the ideal form dictated by the computer geometry, the advantages of using multiple processors are quickly lost to cumbersome data transfers between non-adjacent processors.
Therefore, it is the object of this invention to provide an optical data switch which allows any processor in a multiprocessing environment to read data from any other processor.
It is another object of this invention to provide an optical data switch which allows any processor in a multiprocessing environment to post its resulting data at a location where it can be read by any other processor.
It is a further object of this invention to provide a method for exchanging data among processors in a multiprocessing environment.